﻿//        Copyright (c) 2009, Semyon A. Chertkov (semyonc@gmail.com)
//        All rights reserved.
//
//        Redistribution and use in source and binary forms, with or without
//        modification, are permitted provided that the following conditions are met:
//            * Redistributions of source code must retain the above copyright
//              notice, this list of conditions and the following disclaimer.
//            * Redistributions in binary form must reproduce the above copyright
//              notice, this list of conditions and the following disclaimer in the
//              documentation and/or other materials provided with the distribution.
//            * Neither the name of author nor the
//              names of its contributors may be used to endorse or promote products
//              derived from this software without specific prior written permission.
//
//        THIS SOFTWARE IS PROVIDED ''AS IS'' AND ANY
//        EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
//        WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
//        DISCLAIMED. IN NO EVENT SHALL  AUTHOR BE LIABLE FOR ANY
//        DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
//        (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
//        LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
//        ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
//        (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
//        SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;

namespace DataEngine.CoreServices
{
    public delegate void ChangeValueAction(SymbolLink sender, MemoryPool pool);

    public class SymbolLink
    {
        internal int index;
        internal int pool_id = MemoryPool.UnkID;

        public SymbolLink()
        {
            Type = typeof(System.Object);            
        }

        public SymbolLink(object value, MemoryPool pool)
        {
            Type = value.GetType();
            pool.Bind(this);
            pool.SetData(this, value);
        }

        public SymbolLink(Type type)
        {
            Type = type;            
        }

        internal void ChangeValue(MemoryPool pool)
        {
            if (OnChange != null)
                OnChange(this, pool);
        }

        public bool IsStatic { get; set; }

        public bool IsBinded
        {
            get
            {
                return pool_id != MemoryPool.UnkID;
            }
        }
        
        public Type Type { get; private set; }

        public event ChangeValueAction OnChange;

        public override string ToString()
        {
            return String.Format("{0}@{1}", Type, index);
        }
    }
}
